Cranes on the edge

The main crane flock flies past Burrow Mump in Somerset. Photo: John Crispin.
The main crane flock flies past Burrow Mump in Somerset. Photo: John Crispin.
A flock of Common Cranes that ended up in a once-in-200-year flood has given researchers an insight into how wildlife copes with extreme weather.

The cranes’ progress was tracked by researchers from the University of Exeter, the Wildfowl and Wetlands Trust (WWT) and the RSPB when severe flooding hit the Somerset Levels in 2013.

A study published recently in the journal Scientific Reports found that the floods forced the cranes out of their usual roosts and feeding sites, and caused them to spend two extra hours a day foraging along the margins of the flooded areas.

Andrea Soriano, the PhD student at the University of Exeter, Devon, who carried out the research said: “Climate change means we are seeing extreme weather occur more frequently. Monitoring the effects of those events is essential so that we can design and implement successful conservation plans.”

Common Cranes display on the Somerset Levels. Photo: John Crispin.

WWT Chief Scientist and project co-supervisor Geoff Hilton said: “Shallow winter flooding is normal on the Somerset Levels, but no one expected the crane flock to end up [in] floods so severe that they became a global news story. They were literally pushed to the edge, but pulled through in the end.

“Extreme weather events are inherently unpredictable, so it is very rare for wildlife researchers to be in the right place at the right time, [and] able to monitor in detail how animals cope. We’ve gained valuable insights here.”

Damon Bridge, Project Manager with the RSPB in Somerset, said “It is encouraging that although the floods were extreme that winter, large in extent, and disruptive to the birds’ usual pattern – they survived. They are remarkably resilient, adaptable and tough creatures, character traits that will serve them well as they gain a permanent foothold once again in the Levels and Moors.”

The researchers were engaged in a three-year project to study the survival and breeding behaviour of 70 Common Cranes released by The Great Crane Project, an attempt by the WWT, the RSPB and the Pensthorpe Conservation Trust, Norfolk, to reintroduce the species to the South-West. Andrea Soriano tracked their movements to understand how they use the wetland landscape, and which food sources they exploit. The team can now use the information to advise on how best to create crane-friendly wetlands, and help the birds' population spread and thrive.

Professor Stuart Bearhop of the University of Exeter oversaw the study, and said: “This study provides evidence that some species might withstand the consequences of extreme climatic events to a certain extent. Nevertheless, responses are likely to be varied and some species could well be more vulnerable than others. More research is needed in this area.”